We propose to investigate conformational requirements and/or conformational changes associated with phospholipid-protein interactions in model membrane systems and in an intact biomembrane, the sarcoplasmic reticulum (SR) of rabbit skeletal muscle. The investigation proposes a two-pronged attack on these "conformational dynamics" of lipid-protein interactions: first, a laser Raman spectroscopic investigation of conformational changes, in both protein and lipid, associated with polar and hydrophobic binding of proteins to phospholipid liposomes; and second, an investigation of conformational changes in sarcoplasmic reticulum associated with removal of extrinsic or intrinsic protein from the intact biomembrane, or associated with addition of ATP or Ca 2ion to the membrane and its components.